Limit Question Solution | Simplifying Infinite Limit with e^2 Result

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SUMMARY

The limit problem presented involves evaluating the expression lim_{x-> \infty} ( \frac {x+lnx}{x-lnx})^{(x/lnx)}. The solution simplifies to lim_{t-> \infty} (\frac {1 + \frac {1}{t}} {1 - \frac{1}{t}})^t, which converges to e^2. The key steps include factoring out x and substituting t = \frac{x}{lnx} to facilitate the limit evaluation. The final result confirms the limit equals e^2.

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Homework Statement


I've done thsi limit, i think I'm half right. I'm sure I have done something wrong, but I'm not sure what.

[tex]lim_{x-> \infty} ( \frac {x+lnx}{x-lnx})^(x/lnx)[/tex]


The Attempt at a Solution


[tex]lim_{x-> \infty} ( \frac {x+lnx}{x-lnx})^{x/lnx} = lim_{x-> \infty} ( \frac {x(1 +\frac {lnx}{x})}{x(1- \frac {lnx}{x})})^{x/lnx}=[/tex]
[tex] t= \frac {x}{lnx}; lim_{t-> \infty} (\frac {1 + \frac {1}{t}} {1 - \frac{1}{t}})^t=[/tex]
[tex]\frac {e}{e^{-1}}=e^2[/tex]
 
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